Underfeed stoker



Qct. 14 1924.

R. S. RILEY UNDERFEED STOKER Filed Aug. 4, 1919 6 Sheets-Sheet I q R. 5B @26 "I, ovneyfi. M v

Oct. 14 1924; 1,511,980

R. S. RILEY UNDERFEED S T OKER Filed Aug. 4, 1919 6 Sheets-Sheet 2 Oct. 14, 1924.

R. s. RILEY UNDERFEED STOKER WHHHHHHHHW Filed Aug. 4, 1919 H HH H H HHHHH Patented Oct. 14, 1924.

UNITED, STATES PATENT OFFICE.

ROBERT SANFORD RILEY, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO SANFORD RILEY STOKER 00., OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSA- CHUSETTS.

UNDERFEED STOKE-R.

Application filed August 4, 1919. Serial No. 315,165.

To all whom it may co wern:

Be it known that 1, ROBERT SANFORD RILEY, a citizen of the United States, residing at Worcester, in the county ofWorcester and State of Massachusetts, have invented a new and useful Underfeed Stoker, of which the following is a specification.

This invention relates to an underfeed stoker of the type in which refuse is discharged at the sides of the retort. It is the general object of my present invention to improve theconstruction of such stokers to the end that more efficient operation may be attained.

With this general object in view, one feature of my invention consists in providing an underfeed stoker of this general type with over-feed grates at each side of the retort which are divided along the retort into a my improved stoker;

1plurality of relatively short sections, and in rther providing means to oppositely reciprocate alternate sections, thus thoroughly agitating the fuel bed.

Another feature of my invention consists in the provision of a retort having side walls capable of transverse reciprocation throughout the greater portion of their height. Other features of my invention relate to the provision of improved operating devices for the movable side walls and over-feed grates, and also to certain constructions, arrangements, and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

Three forms of my inventionare shown in the drawings in which F ig: 1 is a front elevation of one form of Fig. 2 is a partial thereof;

Fig. 2 is a diagrammatic detail plan view of a modification;

Fig. 3 is a longitudinal sectional elevation of the parts shown in Fig.1;

Fig. 4 is a' transverse sectional elevation, taken along the line 44 of Figs. 2 and 3;

Fig. 5 is a detail longitudinal sectional elevation taken along the line 5-5 in Fig. 4; Fig. 6 is a partial transverse sectional elevation of a second form of my invention;

Fi 7 is a horizontal section taken'on the line 7inFig.6;

Fig. 8 is a transverse sectional elevation,

diagrammatic plan view similar to Fig. 4, and showing an additional modification;

b Fig. 9 is a side elevation of a frame mem- Fig. 10 is a detail sectional elevation taken along the line 1010 in Fig. 3; and

Fig. 11 is a detailed elevation of parts of the mechanism shown in Fig. 8.

Referring particularly to Figs. 3 and 4, my improved stoker as shown therein com prises a hopper 10 from which coal is fed intermittently by a plunger or ram 11 to a trough or retort having side walls 12 and 13, and-a bottom plate 14. As coal is fed to the retort by the plunger 11, the fuel body in the retort gradually increases until it overflows the retort on each side thereof, being then deposited upon over-feed and 16, disposed along the sides 0 the retort. The fuel gradually works down along the inclined surfaces of the grates 15 and 16, during which movement combustion is substantially completed. The ash and refuse are deposited on dumping or discharge plates 17 and 18 which extend nearly to the side walls 19 and 20. Sufficient openings.

may be left however, between the plates 17 and 18 and the side walls to permit the refuse to drop through into the ash pit continuously.

The plates 17 and 18 are supported by rack bars 21, which may be moved toward or from the side walls by manually operated pinions 22, thus adjusting the width of the discharge openings as desired.

The plate 14 forming the bottom of the retort is provided with a flange or lug 23 ates 15 at its front end by which it is connected to the plunger 11, being consequently reciprocated therewith. The plate 14 is also preferably provided with aplurality of upward- 1y projecting portions 24, adapted to engage t 'e fuel an move it longitudinally of the retort. A fixed cover plate 25 may be provided at the rear end of the retort to prevent coal from being deposited behind the rear of the plate 14 as the plate is drawn forward.

The plateis supported for forward and rearward movement on fixed transverse frame members 26 (Fig. 9) to which are secured guides 27 and 28 extending along each side ofthe plate 14. Additional cover plates 29 protect t e longitudinal edges of the plate 14 and prevent coal from entering between the plate 14 and the guides 27 and 28.

The side walls and over-feed grates are formed in relatively short sections arranged longitudinally of the retort, as clearly shown in Figs. 2 and 3. Each section consists of a hollow casting or frame Work 30,'to the outer end of which a dumping plate 17 or 18 is pivoted at 31. The over-feed grates and 16 are detachably mounted on the frames as is also a casting 32, forming the upper part of both the side wall and the over-feed grate. These members 32 may be connected to the frames 30 by bolts or 15 pins 33 extending through openings formed in corresponding lugs on the parts 30 and 32. ,The hollow frames 30 are mounted to slide upon T-shaped bars 34 (Fig. 5) forming intermediate parts of the transverse 20 frame members 26. The ends of the members 26 are widened and rest on fixed I- beams 35 (Fig. 4) or on other suitable supports. Depending projections or brackets 36 are secured to or formed integral with 2 the frames 30 and extend below the central retort for engagement with the operating mechanism to be described. Each pair of opposed brackets 36 are connected by the plates 63 (Fig. 4). 30 I will now describe the mechanism by which the plate 14 may be reciprocated lon- -gitudinally and the side wall and grate members may be reciprocated transversely of the retort. A cylinder 40 is mounted on the front of the stoker and contains a piston having a piston rod 41,- slidable in suitable bearings across the front of thestoker. The piston and piston rod may be moved alter- 40 nately in opposite directions by either air or steam pressure but my invention is not limited to movement of the rod 41 in any specific manner. A bell crank '42 is mounted 11 on a fixed vertical pivot 43 and is 45 provided with a forked end 44, embracing the pistdn rod 4 1 and received between collars 45 and 46 adjustably secured on the shaft 41.

The second arm 47 of the bell crank 42 is connected by a link 48 to theplunger 11,

previously described, and by this connection the plunger is alternately movedin and out beneath the hopper 10. By adjustin the collars 45 and 46 along the piston rod t 41, lost motion may be provided and the stroke of the plunger may be thus reduced,

or the relative position of the stroke may 'be changed. v

A second lever 50 is mounted upon a fixed c.) horizontal pivot 51, and is provided with a forked upper end 52, en aged between a collar 53 secured to the ro 41, and a collar 54 adjustable thereon. The lower end of the lever 50 is connected by alink 55 to an arm 56 mounted on a cam-shaft 57. The

shaft 57 extends longitudinally below the 58, as shown in Fig. 3.

- The cam-shaft is provided With two series of cams 59 and 60, which are oppositely disposed on the shaft. Each depending cam 59 engages faces 62 formed on opposed projections 36 (Fig. 4). The upwardly extending cams 60 engage upper faces 62 (Fig. 10) on projections 36 associated with the next adjacent pair of sliding castings 01' frames 30.

As the piston-rod 41 is reciprocated, the arm 56 is oscillated, and in turn produces an oscillating movement of the cams-59 and 60. Such movement of the cams reciprocates successive side wall and grate section's the entire space below the retort may form an air passage to the side walls of the retort, which are perforated as shown in 4 to admit air to the fuel in the retort. It is frequently desirable to admit air at reduced pressure to the fuel on the overfeed grates, and for this'purpose I provide an intermediate partition 64 in each sliding member 30, such partition forming a chamber 65 below the grates, connected b openings 66 and67 to a chamber 68. he admission of air to each chamber 68. is controlled by dampers 69, mounted on a shaft 70, and operated by a handle 71 (Fig. l).

With this arrangement, full air pressure is delivered to the side walls of the retort, vwhile the pressure on the over-feed grates may be reduced to any desired extent.

In Figs. 6 and 7, I have shown a second form of my invention, involving structural modifications. p

In this construction, the sliding members 72 are formed as separate pieces, each'provided with a depending bracket 73, which may be secured to the member 72 by bolts "74. The oppositely disposed brackets 73 of each pair are connected by a tie-plate 75 and the oscillating cam reciprocates the members 72 by engagement with the faces of the brackets 73 as previously described.

In this construction, the entire portion 76 which forms the retort side wall is detachable and replaceable as a unit, the lower end being conveniently held in position by a bolt 76 dropped loosely into openings provided therefor, and the upper end being also suitably secured to the sliding mem-- ber 72.

A loose plate78 separates the interior of the sliding member 72 into two compartments for air distribution, andthe pressure I details of construction from the form first of the. air in the left hand compartment (as viewed in Fig. 6) may be controlled by a sliding damper 79. The dumping plates 80 are each provided with a split bearing adapted toreceive pivots 81 (Fig. 7 on the member 72 which extend toward each other and into the bearing of the plate.

This form of my invention dlfl'ers only in described, the operation of both being identical.

' In Figs. 8 and 11 I have shown a second modification in which not only ad1acent side wall sections are oppositely rec procated but in which the two corresponding wall sections on opposite sides of the retort are, also oppositely reciprocated, so that they alternately approach and recede from,

I double cams 86 are secured, cooperating with said extensions the brackets associated with adjacent pairs of side wall sections are oppositely disposed, the bracket extensions for one pair being shown in Fig. 8 and for the next adjacent pair in Fig. 11.

As the shaft 57 is'ocillated, the opposite side wall sections approach and recede from each other and the nextadjacent sections each move simultaneously but in the opposite direction. The fuel bed is even more thoroughly agitated in this'form of my invention than in the forms previously described, as the fuel is forced upward out of the retort by the approaching side wall sections.

In all forms of my invention, the corners of the side wall sections may be rounded as at 30 in Fig. 2, giving a slightly conical or plow-like effect to the inner ends of the sections, designed to assist in heaving the fuel upward and breaking up the fuel bed.

Having thus described my invention, it will be evident that changes and modifications can be made therein-by those skilled in the art within the scope of my invention as set forth in the claims, and I do not wish to be otherwise limited to the details herein disclosed, but what I claim is:

1. An underfeed stoker having in combination, a retort with side walls formed in sections successively disposed along said retort, over-feed grates also formed in sections, each grate section being connected to move with an associated side wall section, and means to reciprocate adjacent side wall sections and their associated grate sections simultaneously in opposite directions.

2. An underfeed stoker having, in combination, a retort with side walls formed ,in sections successively disposed along said retort, over-feed grates also formed, in sections, each grate section being connected to move with an associated sidewall section, sectional discharge plates pivotally connected to said grate sections, means to reciprocate each corresponding side wall section, grate section and discharge plate section as a unit, and means to vary the-path of movement of said discharge plates.

3. An underfeed stoker having, in combination, a retort with side walls formed in sections successively disposed along said retort, over-feed grates also formed in sections, each grate section being connected to and means to reciprocate each side wall section and its corresponding grate section as a unit horizontally, adjacent units being reciprocated simultaneously in opposite directions.

4. An underfeed stoker having, in combination, a retort with side walls formed in sections successively disposed along said retort, over-feed grates also formed insections, each grate section being connected to move with an associated side wall section, a cam shaft extending longitudinally beneath move with an associated side wall section,

said retort and having a plurality of cam portions disposed. thereon, and a member carried by each combined side wall and grate section and positioned for engagement by one of said cam portions.

5. An underfeed stoker having, in combination, a retort with side walls formed in sections successively disposed along said retort, overfeed grates also formed in sections, each grate section being connected to move with an associated side wall section, dischargeplates pivotally connected to said grate sections, and means to reciprocate each corresponding side wall section, grate section and discharge plate section as a unit transversely of said retort to elfect lateral fuel feed and ash discharge.

6. An underfeed stoker having, in com- 7 bination, a longitudinal retort with movable side walls extending approximately to the bottom of said retort, overfeed grates con-, nected to move with said side walls transversely to the axis of said longitudinal retort,'and means to horizontally reciprocate said side walls and associated overfeed grates transversely of said retort to effect lateral distribution of fuel over said grates.

7. An underfeed stoker having, in combination, a longitudinal retort with movable side walls, overfeed grates connected to move with said side walls transversely to the axis of said longitudinal retort, ash dis charge plates pivotally mounted at the Outer ends 'of said overfeed grates, adjustable means to' support said plates, and means to horizontally reciprocate said side-walls, said overfeed grates and said discharge plates transversely of said retort to eflect lateral fuel feed and ash discharge.

sections slidably mounted on said flat supporting members and receiving air through said openings, and means to reciprocate adjacent sections of said side walls and associated grates as units simultaneously, in opposite directions with respect to adjacent sections.

9. An underfeed stoker having, in combination, a retort with side walls formed in sections successively disposed along said retort, overfeed grates also formed in sections, each grate section being connected to move with an associated side wall section, and means to move oppositely-disposed wall sections alternately toward and away from each other, and to simultaneously move adjacent sections in the opposite directions.

10. An underfeed stoker having, in' combination, a longitudinal retort with movable of said side wall sections transversely to said longitudinal retort, and means to cause oppositely disposed wall sections and the grate sections associated therewith to alternately approach and reoede from each other to effect lateral fuel feed, adjacent wall .sections and their associated grate sections as units moving simultaneously in opposite directions with respect to adjacent sections.

11. An underfeed stoker having, in combination, a retort with side walls formed in sections successively disposed along said retort, overfeed grates also formed in sections, each grate section being connected to move with an associated side wall section, and means to reciprocate adjacent side wall and grate sections as units simultaneously in opposite directions with respect to adjacent sections, the inner corners of each wall section being shaped to cause said wall section to have a wedging liftin action on the fuel.

- In testimony whereof have hereunto affixed my signature.

i ROBERT SANFORD RILEY. 

